Method and apparatus for selecting an access and mobility management function in a mobile communication system

Abstract

The present disclosure relates to a communication technique of fusing a 5G communication system for supporting higher data transmission rate beyond a 4G system with an IoT technology and a system thereof, and provides an intelligent service (for example, smart home, smart building, smart city, smart car or connected car, health care, digital education, retail business, security and safety related service, or the like) based on the 5G communication technology and the IoT related technology. A method for appropriately finding a network node providing services that user equipment (UE) wants in a 5G mobile communication system when a user initially accesses a G network includes a method for managing network deployment information and a method for transmitting an initial access request message with a detailed proposal technology. In addition, even when the service provided to the user equipment is modified after the initial access, a network node providing the corresponding service may be found in a similar manner.

What is claimed is: 
     
       1. A method performed by an access network entity in a wireless communication system, the method comprising:
 receiving, from a terminal in the wireless communication system, a message including first information for identifying an access and mobility management function (AMF), the first information including an AMF set identifier and an AMF identifier; 
 selecting an AMF set based on the AMF set identifier; and 
 selecting an AMF from the selected AMF set; and 
 transmitting, to the terminal, second information for identifying the AMF and the terminal, 
 wherein the AMF set comprises at least one AMF that supports a same network slice, and 
 wherein the AMF set identifier is an identifier of the AMF set, and the AMF identifier is an identifier of an AMF within the AMF set. 
 
     
     
       2. The method of  claim 1 , wherein the AMF is selected from the selected AMF set based on at least one of availability of at least one AMF included in the selected AMF set or load balancing across the at least one AMF included in the selected AMF set. 
     
     
       3. The method of  claim 1 , wherein the access network entity includes a radio access network entity or a non-3GPP inter-working function (N3IWF) entity. 
     
     
       4. The method of  claim 1 , wherein the message further includes third information for a network slice selection assistance information (NSSAI) requested by the terminal, and
 wherein the AMF set is selected further based on the third information. 
 
     
     
       5. A method performed by a terminal in a wireless communication system, the method comprising:
 transmitting, to an access network entity in the wireless communication system, a first message including first information for identifying a first access and mobility management function (AMF), the first information including an AMF set identifier and an AMF identifier; 
 receiving, from the access network entity, a second message as a response to the first message, wherein an AMF set is selected based on the AMF set identifier, 
 wherein the second AMF is selected from the selected AMF set, 
 wherein the AMF set comprises at least one AMF that supports a same network slice, 
 wherein the AMF set identifier is an identifier of the AMF set, and the AMF identifier is an identifier of an AMF within the AMF set, and 
 wherein the second message includes second information for identifying a second AMF and the terminal. 
 
     
     
       6. The method of  claim 5 , wherein the second AMF is selected from the AMF set based on at least one of availability of at least one AMF included in the selected AMF set or load balancing across the at least one AMF included in the selected AMF set. 
     
     
       7. The method of  claim 5 , wherein the access network entity includes a radio access network entity or a non-3GPP inter-working function (N3IWF) entity. 
     
     
       8. The method of  claim 5 , wherein the first message further includes third information for a network slice selection assistance information (NSSAI) requested by the terminal, and
 wherein the AMF set is selected further based on the third information. 
 
     
     
       9. An access network entity in a wireless communication system, the access network entity comprising:
 a transceiver; and 
 a controller configured to:
 receive, from a terminal in the wireless communication system via the transceiver, a message including first information for identifying an access and mobility management function (AMF), the first information including an AMF set identifier and an AMF identifier, 
 select an AMF set based on the AMF set identifier, 
 select an AMF from the AMF set, and 
 transmit, to the terminal, via the transceiver, second information for identifying the AMF and the terminal, 
 
 wherein the AMF set consists of at least one AMF that, and the at least one AMF in the AMF set supports a same network slice, and 
 wherein the AMF set identifier identifies the AMF set, and the AMF identifier identifies an AMF within the AMF set. 
 
     
     
       10. The access network entity of  claim 9 , wherein the AMF is selected from the AMF set based on at least one of availability of at least one AMF included in the selected AMF set or load balancing across the at least one AMF included in the AMF set. 
     
     
       11. The access network entity of  claim 9 , wherein the access network entity includes a radio access network entity or a non-3GPP inter-working function (N3IWF) entity. 
     
     
       12. The access network entity of  claim 9 , wherein the message further includes third information for a network slice selection assistance information (NSSAI) requested by the terminal, and
 wherein the AMF set is selected further based on the third information for the NSSAI. 
 
     
     
       13. A terminal in a wireless communication system, the terminal comprising:
 a transceiver; and 
 a controller configured to:
 transmit, toward an access network entity, via the transceiver, a first message including first information for identifying a first access and mobility management function (AMF), the first information including an AMF set identifier and an AMF identifier, and 
 receive, from the access network entity, via the transceiver, a second message as a response to the first message, 
 
 wherein the second message includes second information for identifying a second AMF and the terminal, 
 wherein an AMF set is selected based on the AMF set identifier, 
 wherein the second AMF is selected from the AMF set, wherein the AMF set consists of at least one AMF, that and the at least one AMF in the AMF set supports a same network slice, and 
 wherein the AMF set identifier identifies the AMF set, and the AMF identifier identifies an AMF within the AMF set. 
 
     
     
       14. The terminal of  claim 13 , wherein the second AMF is selected from the AMF set based on at least one of availability of at least one AMF included in the selected AMF set or load balancing across the at least one AMF included in the AMF set. 
     
     
       15. The terminal of  claim 13 , wherein the access network entity includes a radio access network entity or a non-3GPP inter-working function (N3IWF) entity. 
     
     
       16. The terminal of  claim 13 , wherein the first message further includes third information for a network slice selection assistance information (NSSAI) requested by the terminal, and
 wherein the AMF set is selected further based on the third information for the NSSAI.